Project Summary The extent of pervasive transcription throughout the mammalian genome raises questions about roles of the resulting transcripts, which altogether dictate cellular function. Despite their prevalence, functions for the long non-coding RNA (lncRNA) class of noncoding RNAs remain enigmatic. Long term, our research goal is to understand the purpose of non-protein coding transcripts in determining cell identity. Cyrano is a lncRNA that has previously been implicated in cell proliferation and development; however, mechanistic details on Cyrano function are sparse. Preliminary work combining single molecule approaches, expression profiling, phenotyping and delineation of the Cyrano-interactome revealed that depletion of Cyrano is detrimental to embryonic stem cell maintenance. Cyrano is expressed throughout several adult tissues, yet it is elevated in stem cell populations, initiating the hypothesis that it is important for development by supporting cell survival and self-renewal. This defined project consists of two specific aims which include: 1) Understanding the function of Cyrano?s interaction with, and/or regulation of select protein and miRNA candidates in the context of self-renewal and pluripotency, and 2) Assessing the phenotypic consequence of modulation of Cyrano expression in the establishment and maintenance of pluripotency, using CRISPR/Cas9 and overexpression studies. Altogether, we will combine bioinformatic, genetic, biochemical and cell biology tools to better understand the molecular framework in which Cyrano functions, and broadly understand consequences of its loss in developmentally important cells. Data obtained in this study will advance knowledge on mechanistics of lncRNA function, and lay the groundwork for further studies into how their deregulation contributes to disease states.